Question: Solve for $x$ : $8x + 7 = 10x + 9$
Solution: Subtract $8x$ from both sides: $(8x + 7) - 8x = (10x + 9) - 8x$ $7 = 2x + 9$ Subtract $9$ from both sides: $7 - 9 = (2x + 9) - 9$ $-2 = 2x$ Divide both sides by $2$ $\dfrac{-2}{2} = \dfrac{2x}{2}$ Simplify. $-1 = x$